Publications

Ip, K, Ray, AS, Stuart, BH & Thomas, P 2005, 'Investigation of the degradation of sandstones in Sydney's heritage buildings' in Modena, C, Lourenco, PB & Roca, P (eds), Structural Analysis of Historical Constructions - Possibilities of Numerical and Experimental Techniques vol 1, Taylor & Francis, London, UK, pp. 239-244.
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Sydney, with many of its heritage buildings and monuments constructed as a result ofthe first European settlement in the l800s, is a city built on a large block of sandstone. Although many ofthese buildings are still strong and sound, signs of deterioration have become evident in recent years. In order to prevent these precious buildings from further degradation, the weathering mechanisms of the stones must be thoroughly understood before suitable protection measures can be implemented. In this study, four techniques have been selected to detect chemical and physical differences between weathered and unweathered sandstones - Solid State Nuclear Magnetic Resonance (NMR) Spectroscopy, Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC) and X-ray Photoelectron Spectroscopy (XPS).

Choudhury, D & Nimbalkar, S 2005, 'Seismic passive resistance by pseudo-dynamic method', Géotechnique, vol. 55, no. 9, pp. 699-702.
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Connan, HG, Klimesch, DS, Ray, AS & Thomas, PS 2005, 'Autoclaved OPC-quartz blends incorporating clay-brick waste. Part I: factorial design effects on strength development', ADVANCES IN CEMENT RESEARCH, vol. 17, no. 4, pp. 133-141.
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The utilisation of waste materials in the manufacturing of building products is of global interest due to technological and socio-economic benefits. For example, alumina-silica-rich industrial waste, such as fired clay brick, is available in large quanti

Ding, GKC 2005, 'Developing a multicriteria approach for the measurement of sustainable performance', Building Research & Information, vol. 33, no. 1, pp. 3-16.
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In Australia, cost-benefit analysis (CBA) is one of the conventional tools used widely by the public and the private sectors in the appraisal of projects. It measures and compares the total costs and benefits of projects that are competing for scarce resources in monetary terms. Growing concerns that the values of environmental goods and services are often ignored or underestimated in the CBA approach have led to the overuse and depletion of environmental assets. A model of a sustainability index as an evaluation tool that combines economic, social and environmental criteria into an indexing algorithm is presented and described. The sustainability index uses monetary and non-monetary approaches to rank projects and facilities on their contribution to sustainability. This process enables the principle of trade-off to occur in the decision-making process and thereby allows environmental values to be considered when selecting a development option. This makes it possible to optimize financial return, maximize resource consumption and minimize detrimental effects to the natural and man-made world. A case study is used to demonstrate the model.

Friolo, KH, Ray, AS, Stuart, BH & Thomas, PS 2005, 'Thermal analysis of heritage stones', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 80, no. 3, pp. 559-563.
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Many of Sydney's heritage buildings and monuments were built as a result of the first European settlement in the 1800s. These buildings not only display the richness of the Australian culture, but also capture the architectural and historical values of i

Ha, QP, Tran, TH & Dissanayake, G 2005, 'A wavelet- and neural network-based voice interface system for wheelchair control', International Journal of Intelligent Systems Technologies and Applications, vol. 1, no. 1/2, pp. 49-49.
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Voice control has long been considered as a natural mechanism to assist powered wheelchair users. However, one implementation difficulty is that a voice input system may fail to recognise a user’s voice. Indeed, speech activated interface between human and autonomous/semi-autonomous systems requires accurate detection and recognition. In this area pitch and end-point detection is of vital importance. This paper presents a new method for pitch detection based on the continuous wavelet transform phase. The proposed technique can serve as an accurate pitch detector, and also can offer an efficient solution to the end-point detection problem. The extracted features from a user’s speech are then used to train a neural network for speech recognition. Experimental results are provided for the detection of pitch periods and end points and the recognition of a number of commands of male and female users. Laboratory tests are reported for the proposed voice control wheelchair system. © 2005 Inderscience Enterprises Ltd.

Hao, H & Wu, C 2005, 'Numerical study of characteristics of underground blast induced surface ground motion and their effect on above-ground structures. Part II. Effects on structural responses', Soil Dynamics and Earthquake Engineering, vol. 25, no. 1, pp. 39-53.
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Lawry, J, Ray, A, Klimesch, D, Thomas, P, Guerbois, J-P & Harrison, J 2005, 'Thermal characterization of portland cement-magnesia blends', Journal of Thermal Analysis and Calorimetry, vol. 80, no. 3, pp. 637-641.
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Due to growing environmental concerns and the need to use less energy-intensive building products, alternatives and improvements to Portland cement (PC) are being actively researched worldwide. Use of supplementary materials is now a common practice wher

Liu, A, Wu, C, Yu, KF & Gehan, E 2005, 'Supplementary analysis of probabilities at the termination of a group sequential phase II trial', Statistics in Medicine, vol. 24, no. 7, pp. 1009-1027.
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AbstractWe consider estimation of various probabilities after termination of a group sequential phase II trial. A motivating example is that the stopping rule of a phase II oncologic trial is determined solely based on response to a drug treatment, and at the end of the trial estimating the rate of toxicity and response is desirable. The conventional maximum likelihood estimator (sample proportion) of a probability is shown to be biased, and two alternative estimators are proposed to correct for bias, a bias‐reduced estimator obtained by using Whitehead's bias‐adjusted approach, and an unbiased estimator from the Rao–Blackwell method of conditioning. All three estimation procedures are shown to have certain invariance property in bias. Moreover, estimators of a probability and their bias and precision can be evaluated through the observed response rate and the stage at which the trial stops, thus avoiding extensive computation. Copyright © 2004 John Wiley & Sons, Ltd.

Liu, B, Thomas, PS, Williams, RP & Donne, SW 2005, 'Thermal characterisation of chemically reduced electrolytic manganese dioxide', Journal of Thermal Analysis and Calorimetry, vol. 80, no. 3, pp. 625-629.
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Samples of electrolytic manganese dioxide (EMD) were chemically reduced using 2-propanol under reflux (82 degrees C) for 1, 2, 3, 6 and 24 h intervals. XRD analysis showed that the gamma-MnO2 structure was preserved although the lattice dimensions were o

Šimon, P, Cibulkovő, Z & Thomas, P 2005, 'Accelerated thermooxidative ageing tests and their extrapolation to lower temperatures', Journal of Thermal Analysis and Calorimetry, vol. 80, no. 2, pp. 381-385.
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A procedure for the extrapolation of accelerated thermo-oxidative ageing tests to lower temperatures is proposed. The procedure involves a deconvolution of the global process into high- and low-temperature components where the extrapolation to low temper

Thomas, P & Šimon, P 2005, '{\rtf1\ansi\ansicpg1250\deff0\deflang1038\deflangfe1038\deftab708{\fonttbl{\f0\froman\fprq2\fcharset238{\*\fname Times New Roman;}Times New Roman CE;}} \viewkind4\uc1\pard\f0\fs20 A pseudo-isothermal kinetic analysis of the recrystallisation of nickel sulphide measured by non-isothermal DSC \par }', Journal of Thermal Analysis and Calorimetry, vol. 80, no. 1, pp. 77-80.
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A pseudo-isothermal method for the kinetic analysis was applied to the recrystallisation of alpha to beta nickel sulphide based on the Ozawa model for non-isothermal crystallisation in the presence of pre-existing nuclei. The aim of the analysis was to d

Troendle, JF, Liu, A, Wu, C & Yu, KF 2005, 'Sequential testing for efficacy in clinical trials with non-transient effects', Statistics in Medicine, vol. 24, no. 21, pp. 3239-3250.
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This paper describes a new type of sequential testing for clinical trials. The sequential nature of the data is not from additional patients, but rather from longer follow-up times. At each analysis, the null hypothesis that all treatments are equivalent in effect on the outcome after that amount of time is tested. The trial might still have staggered entry or not, but the key feature is that a different statistical hypothesis is tested at each analysis. It is assumed that any effect of treatment is non-transient, allowing a conclusion to be drawn in favour of one treatment or the other based on a difference at a single follow-up time. It is shown that a general method based on the Bonferroni inequality can be used to obtain critical cutpoints for sequential testing, that controls the chance of a type I error for the clinical decision. This method is applicable regardless of the test used at each analysis. In the case of a two-armed trial with a Gaussian outcome variable, it is shown how simulation can be used to obtain critical cutpoints that maintain the chance of a type I error for the clinical decision. The methods are compared by Monte-Carlo simulation, and it is seen that in most practical cases the Bonferroni method is not very conservative. The Bonferroni procedure is illustrated on the results of a real clinical trial of Pirfenidone on pulmonary fibrosis in Hermansky-Pudlak Syndrome.

Wang, JJ, Wang, J, Sinclair, D, Watts, L & lee, HK 2005, 'Tropospheric Delay Estimation for Pseudolite Positioning', Journal of Global Positioning Systems, vol. 4, no. 1&2, pp. 106-112.
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Pseudolites, ground-based GPS signal transmitters, can significantly enhance the GPS satellite geometry or can even be an independent positioning system. However, as pseudolites are very close to the receivers, error effects are different from the traditional GPS and should be considered and modeled in a different way. Tropospheric delay is one of the largest error sources of pseudolite positioning, as pseudolite signal propagates through the lower troposphere which is very difficult to be modeled due to spatial variations in atmosphere. The objective of this research is to analyse pseudolite tropospheric delay modelling methods and to select the optimal tropospheric delay models for different applications. Several methods to estimate the tropospheric delay for pseudolite positioning are introduced and compared. One approach is to utilize single-differenced GPS tropospheric models. Another one is to compute the tropospheric delay as a function of the local refractivity along the pseudolite signal path. The ratio method used for Electronic Distance Measurement (EDM) can also be applied to estimate tropospheric delay. Experiments with simulation and real flight test data are conducted in this study to investigate the proposed methods. The advantages and limitations of each method are analysed. The mode defined by RTCA and its modification are suitable for a low elevation and short range application, such as LAAS and local ground based applications. Models derived from single-differenced NMF and Saastamoinen models perform well in long range and high elevation but have big bias in low elevation. And the model derived from the Hopfield model performs relatively well in all the range and elevation.

White, RE, Thomas, PS, Phillips, MR & Wuhrer, R 2005, 'A DSC study of the effect of lead pigments on the drying of cold pressed linseed oil', JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY, vol. 80, no. 1, pp. 237-239.
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Cold pressed linseed oil and paints prepared using the inorganic pigments; lead white and red lead, were characterized using non-isothermal differential scanning calorimetry (DSC) in an air atmosphere to determine the effect of the pigment on the oxidative polymerisation of the drying oil medium. For each paint sample, the onset temperature for oxidation was reduced from 166°C to the range 50 to 60°C when a heating rate of 5 K min-1 was used. In order to determine the rate of drying, the non-isothermal experiments were carried out using a range of heating rates. A change in the mechanism oxidative polymerization was observed as the heating rate was increased. © 2005 Akadémiai Kiadó, Budapest.

Wu, C & Hao, H 2005, 'Modeling of simultaneous ground shock and airblast pressure on nearby structures from surface explosions', International Journal of Impact Engineering, vol. 31, no. 6, pp. 699-717.
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Wu, C & Hao, H 2005, 'Numerical study of characteristics of underground blast induced surface ground motion and their effect on above-ground structures. Part I. Ground motion characteristics', Soil Dynamics and Earthquake Engineering, vol. 25, no. 1, pp. 27-38.
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Wu, C, Hao, H & Deeks, AJ 2005, 'Numerical Analysis of a Two-Rail Steel RHS Traffic Barrier to Vehicle Impact', Australian Journal of Structural Engineering, vol. 6, no. 1, pp. 63-76.
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Wu, C, Hao, H & Lu, Y 2005, 'Dynamic response and damage analysis of masonry structures and masonry infilled RC frames to blast ground motion', Engineering Structures, vol. 27, no. 3, pp. 323-333.
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Wu, Q, Ni, L-X, Chen, Z, Song, S-Q, Liu, X-M, Chai, Z-L & Wu, C-Q 2005, '[Clinical study on atypical pathogens of lower respiratory tract infection in children].', Zhonghua Er Ke Za Zhi, vol. 43, no. 3, p. 218.

Choi, F, Samali, B & Crews, KI 1970, 'Pilot Investigation of Continuity Effect of Corbel in Timber Bridges', Developments in Mechanics of Structures and Materials, Australasian Conference on the Mechanics of Structures and Materials, A A Balkema Publishers, Perth, Australia, pp. 1311-1316.

Choi, F, Samali, B, Li, J, Brown, PW & Dackermann, U 1970, 'Investigation on the Dynamic Response of a Damaged Bridge', Proceedings of the 11th Asia-Pacific Vibration Conference, Asia Pacific Vibration Conference, Universiti Teknologi Malaysia, Langkawi, Malaysia, pp. 274-280.

Choi, FC, Samali, B, Crews, K & Li, J 1970, 'Static and dynamic evaluation of continuity effect of corbels in timber bridges', 4th Australasian Congress on Applied Mechanics, ACAM 2005, Australasian Congress on Applied Mechanics, Institute of Materials Engineering Australasia Ltd, Melbourne, Australia, pp. 285-291.
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This paper presents part of the ongoing experimental and analytical work to investigate the effect of corbels on continuity in timber bridges. Full scale beams with corbels were erected for testing the extreme boundary conditions such as simply supported and fixed end conditions. The states of continuity in the test beams were assessed through a three span beam loading test set up. Dynamic tests were performed on the test beams and the modal parameters extracted were compared against those obtained for simply supported beams without corbel. Analytical investigations were conducted and then compared with the experimental results. The static experimental results obtained showed changes in the vertical displacement for different boundary conditions. The magnitude of reduction in the measured vertical displacement was fairly sensitive to the change of boundary conditions. Hence, changes in vertical displacement at mid-span can be used as an indicator for different boundary conditions, which relate to the effect of corbel on both continuity and effective span length in a structural system, especially for timber bridges. A comparative analysis of the first natural frequency for each boundary condition was then undertaken with reference to a simply supported benchmark. The analysis confirmed that the effects of changes in the boundary can be detected using modal parameters. © Institute of Materials Engineering Australasia Ltd 2005.

Crews, KI, Samali, B & Al-Dawod, M 1970, 'Reliable Assessment of Road Bridges Using Dynamic Procedures', Australian Structural Engineering Conference 2005: Structural Engineering - Preserving and Building into the Future, Australian Structural Engineering Conference, Tour Hosts Pty Ltd, Newcastle, Australia, pp. 1-10.

Friolo, KH, Stuart, BH, Ray, AS & Thomas, P 1970, 'Chemical analysis of cementing clays in Sydney's heritage sandstone buildings', Australian Industrial Minerals Conference, Sydney.

Friolo, KH, Stuart, BH, Ray, AS & Thomas, P 1970, 'Infrared spectroscopy of heritage building stones', Proceedings of the 6th Australian Conference on Vibrational Spectroscopy, ACOVS6 Organising Committee, Sydney.

Gerber, C, Crews, KI & Sigrist, C 1970, 'Investigation on Load/Stress Distribution in SSP and Composite Characteristics of SSP', Developments in Mechanics of Structures and Materials, Australasian Conference on the Mechanics of Structures and Materials, A A Balkema Publishers, Perth, Australia, pp. 77-83.

Graham, KJ, Crews, KI & Bolden, SA 1970, 'A fundamental investigation of the composite behaviour of an AAC panel and timber joist floor system', Autoclaved Aerated Concrete Innovation and Development - Proceedings of the 4th International Conference on Autoclaved Aerated Concrete, pp. 463-473.
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In Australia autoclaved aerated concrete (AAC) panels have been used as external wall cladding and to a lesser extent as the plate element in floors of low-rise structural timber framed construction. In these floors, the timber framing is considered the structural support for the AAC panels. This paper describes a fundamental investigation of the composite behaviour exhibited by a floor system consisting of AAC panels fixed to a proprietary timber joist framing system subjected to out-of-plane bending. The main objectives of the project weretoillustrate the existence of composite action and quantify the magnitude of out-of-plane flexural performance improvement. The investigation program consisted of a series of flexural tests on full-scale floor specimens at both the serviceability and ultimate strength limit states. This paper presents the results of the investigation in relation to the flexural behaviour under static loadings, dynamic response of floor system, load redistribution under point loadings and slip performance of the connection of panel and joist. © 2005 Taylor & Francis Group.

Ha, HM, Nguyen, AD & Ha, QP 1970, 'Controlling formations of multiple mobile robots with inter-robot collision avoidance', Proceedings of the 2005 Australasian Conference on Robotics and Automation, ACRA 2005, Australasian Conference on Robotics and Automation, ARAA, Australian Robotics and Automation Association Inc, Sydney, Australia, pp. 1-7.
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In this paper, we investigate the problem of inter-robot collision avoidance in multiple mobile robot formation control. Two methodologies are utilized, namely Virtual Robot tracking by [Jongusuk and Mita, 2001] and l-l control by [Desai et al., 1998] to establish formation and avoid collision among robots. We point out that the framework in Virtual Robot tracking is potentially subject to collision among robots. This drawback is overcome in our design by incorporating a different reactive scheme in the incident possibility of collision. To prove the advantages of our framework, we demonstrate in simulation the case of three robots moving in formation and avoiding inter-robot collisions.

Ha, QP, Tran, TH, Scheding, S, Dissanayake, G & Durrant-Whyte, HF 1970, 'Control issues of an autonomous vehicle', 22nd International Symposium on Automation and Robotics in Construction, ISARC 2005, International Symposium of Automation and Robotics in Construction, Faculty of Architecture and Engineering, University of Ferrara, Farrara, Italy, pp. 1-7.
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This paper addresses some control issues of a robotic amphibious vehicle that can serve as a general framework for automation of tractors used in construction. These include the vehicle's low-level dynamic equations, the development of its braking control system, kinematics in interactions with ground and the slip problem. Simulation and real-time results to date are presented.

Huang, S, Kwok, N, Dissanayake, G, Ha, QP & Fang, G 1970, 'Multi-Step Look-Ahead Trajectory Planning in SLAM: Possibility and Necessity', Proceedings of 2005 IEEE International Conference on Robotics and Automation, IEEE International Conference on Robots and Automation, The Institute of Electrical and Electronic Engineers Inc, Barcelona, Spain, pp. 1103-1108.
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In this paper, the possibility and necessity of multistep trajectory planning in Extended Kalman Filter (EKF) based SLAM is investigated. The objective of the trajectory planning here is to minimize the estimation error of the robot and landmark locations subject to a given time horizon. We show that the problem can be regarded as an optimization problem for a gradually identified model. A numerical method is proposed for trajectory planning using a variant of the nonlinear Model Predictive Control (MPC). The proposed method is optimal in the sense that the control action is computed using all the information available at the time of decision making. Simulation results are included to compare the results from the one-step look-ahead trajectory planning and the proposed multi-step lookahead technique

Kwok, N, Ha, QP, Li, J & Samali, B 1970, 'Parameter Identification for a Magnetorheological Fluid Damper: An Evolutionary Computation Approach', Proceedings of the 6th International Symposium on Intelligent Technologies, International Symposium on Intelligent Technologies in Tech'05, Faculty of Science and Technology, Assumption University, Phuket, Thailand, pp. 115-122.

Kwok, N, Nguyen, T, Ha, QP, Li, J & Samali, B 1970, 'MR Damper Structural Control Using a Multi-Level Sliding Mode Controller', Australian Earthquake Engineering Society Proceedings of the 2005 Conference, Australian Earthquake Engineering Conference, Australian Earthquake Engineering Society, Albury, New South Wales, Australia, pp. 1-7.

Li, J & Samali, B 1970, 'Fuzzy Sliding Mode Control of Seismically Excited Structure Using Magnetorheological Dampers', Developments in Mechanics of Structures and Materials, Australasian Conference on the Mechanics of Structures and Materials, A A Balkema, Perth, Australia, pp. 479-484.

Li, J, Samali, B & Smith, ST 1970, 'Stiffness estimation and damage detection of fibre reinforced polymer strengthened reinforced concrete beams using a vibration-based method', 4th Australasian Congress on Applied Mechanics, ACAM 2005, Australasian Congress on Applied Mechanics, Institute of Materials Engineering Australasia Ltd, Melbourne, Australia, pp. 663-669.
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Reinforced concrete (RC) structural elements can be strengthened by bonding high-strength, noncorrosive fibre reinforced polymer (FRP) composites to their surfaces. In the majority of strengthening situations the existing structure would have been subjected to extreme loading at some stage of its life. It is of great interest to designers and users of structures to be aware of the condition of the structural elements, particularly with regards to damage, prior to the design and application of FRP strengthening measures. This paper reports the results of a vibration-based method for assessing damage in RC beams prior to and after the application of FRP strengthening. The vibration-based method measures the vibrations of beams with and without additional mass and provides an assessment of the degree of damage as well as stiffness of the structural element. A simply supported RC beam was constructed and initially damaged by loading to 50% of its flexural capacity. FRP strengthening was then applied and the beam tested to failure. Vibration measurements were taken prior to and after damage of the plain beam as well as after application of the FRP strengthening. The proposed method was used for detecting damage and evaluating the repair as well as quantitatively estimating in-service stiffness of the beams. Good correlation between dynamic results and static load test results is found, thus demonstrating the potential of the vibration-based method. © Institute of Materials Engineering Australasia Ltd 2005.

Li, J, Samali, B, Crews, KI & Shestha, R 1970, 'Theoretical and Experimental Studies on Assessment of Bridges Using Simple Dynamic Procedures', Australian Structural Engineering Conference 2005: Structural Engineering - Preserving and Building into the Future, Australian Structural Engineering Conference, Tour Hosts Pty Limited, Newcastle, Australia, pp. 1-11.

Li, YC, Wang, J & Qian, LF 1970, 'Comparative analysis of the dynamic characteristics of MR shock absorber under impact loads', Proceedings of the International Conference on Mechanical Engineering and Mechanics 2005, Vols 1 and 2, International Conference on Mechanical Engineering and Mechanics, SCIENCE PRESS BEIJING, Nanjing Univ Sci & Technol, Nanjing, PEOPLES R CHINA, pp. 927-931.

Samali, B, Dowling, DM & Li, J 1970, 'Dynamic Response of U-Shaped Adobe-Mudbrick Wall Units', Australian Structural Engineering Conference 2005: Structural Engineering - Preserving and Building into the Future, Australian Structural Engineering Conference, Tour Hosts Pty Limited, Newcastle, Australia, pp. 1-9.

Samali, B, Dowling, DM & Li, J 1970, 'Dynamic Testing of Unreinforced U-Shaped Adobe-Mudbrick Wall Unit', Developments in Mechanics of Structures and Materials, Australasian Conference on the Mechanics of Structures and Materials, A A Balkema, Perth, Australia, pp. 505-510.

Samali, B, Widjaja, JH, Li, J & Reizes, J 1970, 'Smart Braced Frame Systems', Developments in Mechanics of Structures and Materials, Australasian Conference on the Mechanics of Structures and Materials, A. A. Balkema, Perth, Australia, pp. 401-406.

Samali, B, Widjaja, JH, Li, J, Dackermann, U & Brown, PW 1970, 'Amplitude Frequency Characteristics of 'Smart'-Pin Frame System', Proceedings of the 11th Asia Pacific Vibration Conference, Asia Pacific Vibration Conference, Universiti Teknologi Malaysia, Langkawi, Malaysia, pp. 228-233.

Shoudong Huang, Kwok, NM, Dissanayake, G, Ha, QP & Gu Fang 1970, 'Multi-Step Look-Ahead Trajectory Planning in SLAM: Possibility and Necessity', Proceedings of the 2005 IEEE International Conference on Robotics and Automation, 2005 IEEE International Conference on Robotics and Automation, IEEE, Barcelona, SPAIN, pp. 1091-1096.
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Smith, ST, Kaul, R, Sri Ravindrarajah, R & Otoom, O 1970, 'Durability Considerations for FRP-Strengthened RC Structures in the Australian Environment', Australian Structural Engineering Conference 2005: Structural Engineering - Preserving and Building into the Future, Australian Structural Engineering Conference, Tour Hosts Pty Limited, Newcastle, Australia, pp. 1-10.

Sri Ravindrarajah, R & Subhan, T 1970, 'Adjusted density high-strength concrete using expanded polystyrene beads', International Conference on Concrete for Concrete Structures, International Conference on Concrete for Concrete Structures, Faculty of Science and Technology of the University of Coimbra, Coimbra, Portugal, pp. 1-8.

Sri Ravindrarajah, R, Difalco, V & Surian, S 1970, 'Effects of binder materials on the properties of polystyrene aggregate concrete', Quality of concrete structures and recent advances in concrete materials and testing, International ACI/CANMET Conference on the Quality of Concrete Structures and Recent Advances In Concrete Materials and Testing, American Concrete Institute, Olinda, Brazil, pp. 33-48.

Wang, J, Wang, QL & Li, YC 1970, 'Finite element analysis of magnetorheological damper', Electrorheological Fluids and Magnetorheological Suspensions (ERMR 2004), Proceedings, 9th International Conference on Electorheological (ER) Fluids and Magnetorheological (MR), WORLD SCIENTIFIC PUBL CO PTE LTD, Beijing, PEOPLES R CHINA, pp. 722-727.

Wang, JN & Li, YC 1970, 'The dynamic simulation and test verification of MR shock absorber under impact load', Electrorheological Fluids and Magnetorheological Suspensions (ERMR 2004), Proceedings, 9th International Conference on Electorheological (ER) Fluids and Magnetorheological (MR), WORLD SCIENTIFIC PUBL CO PTE LTD, Beijing, PEOPLES R CHINA, pp. 822-828.

Widjaja, J, Samali, B, Li, J & Reizes, J 1970, 'Dynamic frequency de-tuning using controllable beamcolumn semi-rigid connections', 4th Australasian Congress on Applied Mechanics, ACAM 2005, Australasian Congress on Applied Mechanics, Institute of Materials Engineering Australasia Ltd, Melbourne, Australia, pp. 807-813.
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The concept of frequency de-tuning and damping enhancement to avoid resonant frequencies and to suppress the vibration response of structures, respectively, has been known for passive vibration control systems since mid 1950's. Ideally the concept shifts the structural frequency away from resonant frequency and significantly reduces the structural response in the 'narrow-band' dampingcontrolled region. However in reality, the passive vibration control performance depends heavily on the dynamic characteristics of energy dissipation systems that are fixed and only applicable for a particular frequency band. Conversely, the Direct Current (DC) controllable beam-column semirigid connections using Magneto-rheological (MR) rotational fluid dampers, can act as real time adjustable passive control devices for any required frequency band. The supplied DC current level can adjust the device torque and rotational velocity characteristics that affect the structural frequency. This paper presents a preliminary parametric study on vibration control performance of a single and a two storey prototype plane frame model due to combination of frequency de-tuning and its associated damping enhancement by selecting end beam connections as either hinged or fixed. The controllable semi-rigid connection characteristics are represented in terms of normalised frequency. And the control performance indicated by Amplitude Frequency Characteristics (AFC) of the models is studied numerically and presented graphically. The study yields an insight into the controllable connections prior to any experiments. © Institute of Materials Engineering Australasia Ltd 2005.

Widjaja, JH, Samali, B, Li, J & Reizes, J 1970, 'Seismic Structural Control Investigations Using a Prototype Magnetorheological Shear Damper', Australian Structural Engineering Conference 2005: Structural Engineering - Preserving and Building into the Future, Australian Structural Engineering Conference, Tour Hosts Pty Limited, Newcastle, Australia, pp. 1-11.